Pressure cook spinach with garlic and ginger.
In pan add ghee/oil .Add cumin seeds and saute onions and the green chilies for about 5-10 minutes. Add tomatoes and saute it for another 2 minutes.
Blend spinach mixture and onion /tomato mixture into a fine puree and keep aside.
In the meantime boil the potatoes and set aside when done. Peel the potatoes and cut into fine cubes.
Heat pan and add spinach-onion/tomato puree and simmer for a few minutes.
Add the cooked potatoes,salt, garam masala and coriander powder and a little water if needed.
Simmer for few minutes till the potatoes absorb the flavor.
Serve it with roti/naan.